package loadcentraltabledata;

import java.io.IOException;
import java.io.LineNumberReader;
import java.io.PrintWriter;
import java.io.Reader;
import java.sql.*;

/**
 * Tool to run database scripts
 */
public class ScriptRunner {

    private static final String DEFAULT_DELIMITER = ";";
    private Connection connection;
    private boolean stopOnError;
    private boolean autoCommit;
    private PrintWriter logWriter = new PrintWriter(System.out);
    private PrintWriter errorLogWriter = new PrintWriter(System.err);
    private String delimiter = DEFAULT_DELIMITER;
    private boolean fullLineDelimiter = false;

    /**
     * Default constructor
     */
    public ScriptRunner(Connection connection, boolean autoCommit,
            boolean stopOnError) {
        this.connection = connection;
        this.autoCommit = autoCommit;
        this.stopOnError = stopOnError;
    }

    public void setDelimiter(String delimiter, boolean fullLineDelimiter) {
        this.delimiter = delimiter;
        this.fullLineDelimiter = fullLineDelimiter;
    }

    /**
     * Setter for logWriter property
     *
     * @param logWriter
     *            - the new value of the logWriter property
     */
    public void setLogWriter(PrintWriter logWriter) {
        this.logWriter = logWriter;
    }

    /**
     * Setter for errorLogWriter property
     *
     * @param errorLogWriter
     *            - the new value of the errorLogWriter property
     */
    public void setErrorLogWriter(PrintWriter errorLogWriter) {
        this.errorLogWriter = errorLogWriter;
    }

    /**
     * Runs an SQL script (read in using the Reader parameter)
     *
     * @param reader
     *            - the source of the script
     */
    public void runScript(Reader reader, String generatedFile) {
        try {
            boolean originalAutoCommit = connection.getAutoCommit();
            try {
                if (originalAutoCommit != this.autoCommit) {
                    connection.setAutoCommit(this.autoCommit);
                }
                LogFile.log(" System  ", " Now will start running The Script Of Main Task .");
                runScript(connection, reader, generatedFile);
            } finally {
                connection.setAutoCommit(originalAutoCommit);
            }
        } catch (SQLException e){
            LogFile.log(" System "," encountered the following Exception While Trying to run the Main Task Script.["+e+"]");
        } catch (Exception e) {
            LogFile.log(" System "," encountered the following Exception While Trying to run the Main Task Script.["+e+"]");
        }
    }

    /**
     * Runs an SQL script (read in using the Reader parameter) using the
     * connection passed in
     *
     * @param conn
     *            - the connection to use for the script
     * @param reader
     *            - the source of the script
     * @throws SQLException
     *             if any SQL errors occur
     * @throws IOException
     *             if there is an error reading from the Reader
     */
    private void runScript(Connection conn, Reader reader, String generatedFile) {
        LogFile.log(" System  ", "started running The Script of the Main Task .");
        StringBuffer command = null;
        try {
            LineNumberReader lineReader = new LineNumberReader(reader);
            String line = null;
            while ((line = lineReader.readLine()) != null) {
                if (command == null) {
                    command = new StringBuffer();
                }
                String trimmedLine = line.trim();
                if (trimmedLine.startsWith("--")) {
                    println(trimmedLine);
                } else if (trimmedLine.length() < 1 || trimmedLine.startsWith("//")) {
                    // Do nothing
                } else if (trimmedLine.length() < 1 || trimmedLine.startsWith("--")) {
                    // Do nothing
                } else if (!fullLineDelimiter && trimmedLine.endsWith(getDelimiter()) || fullLineDelimiter
                        && trimmedLine.equals(getDelimiter())) {
                    command.append(line.substring(0, line.lastIndexOf(getDelimiter())));
                    command.append(" ");
                    Statement statement = conn.createStatement();
                    println(command);
                    String newcommand = command.toString();
                    newcommand = newcommand.replaceAll("outputfile", generatedFile);
                    System.out.println(newcommand);
                    boolean hasResults = false;
                    if (stopOnError) {
                        hasResults = statement.execute(newcommand);
                    } else {
                        try {
                            statement.execute(newcommand);
                        } catch (SQLException e) {
                            LogFile.log(" System ", " encountered the Following Exception While executing the Main Task Script ["+e+"]");
                            e.fillInStackTrace();
                            printlnError("Error executing: " + command);
                            printlnError(e);
                        }
                    }
                    if (autoCommit && !conn.getAutoCommit()) {
                        conn.commit();
                    }
                    ResultSet rs = statement.getResultSet();
                    if (hasResults && rs != null) {
                        ResultSetMetaData md = rs.getMetaData();
                        int cols = md.getColumnCount();
                        for (int i = 0; i < cols; i++) {
                            String name = md.getColumnLabel(i);
                            print(name + "\t");
                        }
                        println("");
                        while (rs.next()) {
                            for (int i = 0; i < cols; i++) {
                                String value = rs.getString(i);
                                print(value + "\t");
                            }
                            println("");
                        }
                    }
                    command = null;
                    try {
                        statement.close();
                    } catch (Exception e) {
                        LogFile.log(" System ", " encountered the Following Exception While Running the Main Task Script ["+e+"]");
                    }
                    Thread.yield();
                } else {
                    command.append(line);
                    command.append(" ");
                }
            }
            if (!autoCommit) {
                conn.commit();
            }
            LogFile.log(" System ", " finished Running the Script File of the Main Task Successffully");
        } catch (SQLException e) {
            LogFile.log(" System ", " encountered the Following Exception While trying to run the Main Task Script ["+e+"]");
            e.fillInStackTrace();
            printlnError("Error executing: " + command);
            printlnError(e);
         
        } catch (IOException e) {
            LogFile.log(" System ", " encountered the Following Exception While trying to run the Main Task Script ["+e+"]");
            e.fillInStackTrace();
            printlnError("Error executing: " + command);
            printlnError(e);
         
        } finally {
            // conn.rollback();
            flush();
        }
    }

    private String getDelimiter() {
        return delimiter;
    }

    private void print(Object o) {
        if (logWriter != null) {
            System.out.print(o);
        }
    }

    private void println(Object o) {
        if (logWriter != null) {
            logWriter.println(o);
        }
    }

    private void printlnError(Object o) {
        if (errorLogWriter != null) {
            errorLogWriter.println(o);
        }
    }

    private void flush() {
        if (logWriter != null) {
            logWriter.flush();
        }
        if (errorLogWriter != null) {
            errorLogWriter.flush();
        }
    }
}